Control Design of Brushless DC Motors Based on Bus 485

In order to realize the long-distance control of brushless DC motors(BLDCM),made control signals from interference and try to reduce the number of cable,half duplex RS-485 master-slave network adopted and we can control every BLDCM based on bus 485.Communications data included the duty rate of PWM to motor and speed,voltage and current to PC.The result of experiments verified RS-485 was viable and exact in the project.It made connections simple and work reliable for the control system formed by a master PC and many slave MCUs.